WO2022015252A1

WO2022015252A1 - Breathable film

Info

Publication number: WO2022015252A1
Application number: PCT/TR2020/050625
Authority: WO
Inventors: Uğur Yildirim
Original assignee: Beşel Basim Sanayi̇ Ve Ti̇caret Anoni̇m Şi̇rketi̇
Priority date: 2020-07-14
Filing date: 2020-07-14
Publication date: 2022-01-20

Abstract

The invention relates to a method and film that enables the development of breathable composite materials that will prevent the deterioration of their physical and chemical structures during the logistics activities of products that are sensitive to thermal variability. The aim of the invention is to prevent the spoilage of the products due to being exposed to physical, chemical and biological factors during delivery of fresh fruits, vegetables and cut flowers to long distances.

Description

BREATHABLE FILM TECHNICAL FIELD OF THE INVENTION

The invention relates to a method and film that enables the development of breathable composite materials that will prevent the deterioration of their physical and chemical structures during the logistics activities of products that are sensitive to thermal variability. BACKGROUND OF THE INVENTION

Food packaging is in direct contact with food products and is used to protect the food product from production until it is delivered to the customer. The packaging protects the food from external factors, deterioration, contamination or foreign matter entering into it.

Its main function is to protect and preserve the product and to provide information such as expiry date, production date, batch number and nutritional values. Health authorities define the packaging as a container that provides safe protection, shipping and transportation of food commodities.

The most common types of packaging used in food products are glass containers, vacuum packs, Tetra Pak boxes, plastic packaging, tin cans, cardboard boxes, wooden cases, durable packaging, ice cream packaging, metal packaging, layered packaging and juice boxes.

Fruits and vegetables are perishable products that deteriorate quickly. In order to increase the durability of fruits and vegetables, a wide variety of preservation methods are used such as cooling, freezing, thermal applications, fermentation with salt and acid addition, drying, irradiation, modified atmospheric packaging, and addition of preservatives. Undoubtedly, different processes will require different packaging for food products. It is possible to categorize the packages used in the marketing of fresh fruits and vegetables into five groups in general according to the material from which they are manufactured. These are as follows: sack or net (string bag) packaging, wooden packaging (crates, pallets, lids), plastic packaging (polyethylene, polypropylene, polystyrene, polyvinylchloride, polyamide films, sheets, trailers and containers), paper-based packaging (wrapping papers, paper bags, cardboard boxes, corrugated cardboard boxes, trailers, labels, covers, straps and tapes) and other packaging (glass and metal). Each packaging material used for fresh fruits and vegetables has its own advantages. For example, plastic bags and films are among the most commonly used materials. The use of bagging machines can also reduce costs. Due to their transparent nature, the films ensure that the product can be tracked and followed. Corrugated cardboard boxes can be produced in a wide variety of styles and weights; they are low-cost and versatile options. Glass packaging does not interact with the product placed therein; it does not corrode and degenerate over time. Metal packaging creates a strong barrier against light, air and water, and it is sufficiently strong and durable against insects and rodents. Thin papers are open structured papers used in packaging fresh fruits and vegetables. Waxed papers provide moderate resistance against water and water vapor. String bags ensure that products receive light and are prevented from contamination. Pallets are an efficient way of carrying products together and can be produced at low costs. Solid plastic containers are often used for small, soft fruits such as cherries, strawberries, and for mushrooms. Wooden crates can be used for hard fruits and vegetables, while sacks and wood-coated baskets can be used to transport fresh fruits and vegetables.

It is the main duty of the supplier companies to ensure the integrity of the chain during the transportation of vegetables, fruits and flowers. The selection of passive protection systems employed for this purpose has a great significance. Passive protection systems enable delivery of the products within the targeted time and temperature range thanks to its correctly designed components, insulated tote-boxes and equipment placed therein (eutectic battery, separator, insulation materials). Unfortunately, it is frequently observed in Turkey that suppliers still perform door-to-door deliveries using non-validated Styrofoam boxes and ice boxes with unknown content. Below are some undesired consequences of the lack of thermal covers in the delivery of food and cut flower:

- Increase in general cargo expenses (unnecessary volume and weight)

Offended consumers due to spoiled deliveries General loss of reputation due to the feedback from dissatisfied consumers on the internet channels for product complaint

- Recall costs

- Many other problems such as potential food poisoning cases.

CN204136530U is summarized as follows: “The utility model discloses a special breathable composite film. The composite layer comprises DuPont paper, and is characterized with polythene breathable film whose DuPont paper is to be coated with heat-seal glue. The DuPont paper and the polythene tabby breathable film are bound to each other through glue. The wrapper has the benefits that the wrapper is good in air permeability, high in tensile strength, free from paper yellowing, soft in texture and good in heat-seal strength, and further has the advantages of being high-strength in aging resistance, good in high-temperature resistance, smooth in surface, free of wrinkling and blistering.”

The present application was made to produce a breathable film. However, there is no mention of any hole on the metalized polyester, which is among the materials used in the present applications. In addition, calcite is not used in the current application therefor it lacks all the advantages of calcite.

CN201736496U is summarized as follows: “The utility model discloses a protective fabric, comprising a breathable film part, a reinforcing mesh part and a non-woven fabric part which includes a first layer, a second layer and a third layer and is made of polyethylene (PE), polyethylene terephthalate (PET). The third layer is polypropylene (PP) wherein the breathable film part and the non-woven fabric part are bonded together with the reinforcing mesh part through a hot melt adhesive or a water-based adhesive, respectively. Through this protective fabric, the utility model gains advantages such as stable structure, good air permeability, low cost.”

Although the present application aimed to produce a breathable model, it does not mention production of a film, but a fabric, as a result of the processes. Additionally, calcite is not included in the present application as well. Therefore, it lacks all the advantages of calcite. DESCRIPTION OF THE INVENTION

The present invention relates to a method that provides improved breathable composite material to eliminate the above-mentioned disadvantages and bring new advantages to the relevant technical field, and to a film formed by the method.

The aim of the invention is to prevent the spoilage of the products due to being exposed to physical, chemical and biological factors during delivery of fresh fruits, vegetables and cut flowers to long distances.

Another aim of the invention is to provide the advantage of obtaining a film that provides high thermal insulation and reflective properties.

Another aim of the invention is to provide the advantage of eliminating the operational and financial burden as a result of the use of potassium permanganate to prevent the spoilage of certain vegetable, fruit and cut flower products during delivery.

Another aim of the invention is to provide the advantage of obtaining a film that ensures gas (C02, 02 and Ethylene) and moisture permeability and thermal performance which are among the performance criteria for the material.

Another aim of the invention is to minimize the rate of waste, currently 25%, in fresh fruit and vegetable transportation in Turkey, thereby reducing waste, loss, and financial damage occurring during these processes.

Another aim of the invention is to eliminate the problems in product quality arising out of logistics operations.

Another aim of the invention is to create a new segment in the sector.

Another aim of the invention is to create a composite product that is both breathable and insulating and reflects the sun beams, unlike its counterparts used in the relevant sector. Another aim of the invention is to ensure an improvement in the current performance at a rate around 10-15% by meeting the optimum criteria in gas permeability.

Another aim of the invention is to develop a composite material that provides superior thermal insulation (40%), better gas permeability (15%), and increased radiation reflection capacity (15%) compared to existing products on the market.

Another aim of the invention is to establish the infrastructure that will enable production with 100% domestic production input in the upcoming project.

Another aim of the invention is to develop a fully recyclable composite material.

Another aim of the invention is to control the viscosity by using calcite, a material that can be mixed homogeneously with the polyethylene.

Another aim of the invention is to achieve a smooth film surface.

Another aim of the invention is to attain a film with high dispersion properties with the use of calcite.

Another aim of the invention is to ensure pigment economy due to high level of whiteness thanks to the use of calcite.

Another aim of the invention is to provide the advantage of obtaining a thin, light film.

Another aim of the invention is to increase the heat resistance thanks to the strengthening effect of the use of calcite film.

Another aim of the invention is to prevent blocking on film layers when pulled, thanks to the use of calcite. Figures

The application of the present invention briefly summarized above and addressed in detail below can be understood from the exemplary applications depicted in the attached figures of the invention. However, it should be noted that the attached figures only describe the typical applications of this invention, and that the invention allows other equally effective applications, therefore these figures should not be interpreted as restricting the use of the invention.

To facilitate understanding, identical reference numbers are used where possible to indicate identical elements in the figures. The shapes are not drawn to scale and can be simplified for clarity. It is believed that the elements and features of an application can be beneficially included in other applications without further explanation.

Figurel- Composite Film

Explanation of Details in Figures

The description of the reference numbers shown in the figures are given below. 1) Perforated Metalized + Polyester Layer

2) Polyethylene + Calcite Mix Layer

3) Breathable Composite Film

DETAILED DESCRIPTION OF THE INVENTION

In this detailed description, preferred alternatives of the inventive embodiment are described only for a better understanding of the subject and without causing any limiting effects. The invention is characterized in that it includes a perforated metallized polyester layer (1) and a polyethylene calcite mixture layer (2). The method of production of the present invention consists of several steps. These stages are as described below:

- First of all, metallizing is performed on the surface of the polyester film either by coating or spraying method. The polyester film becomes perforated (perforated metallized film) upon being pierced with a hot needle cylinder on the metalized coated polyester film. Thanks to these holes, the present structure acquires a breathable undulated feature. In addition, its metallized layer ensures a surface reflecting sunlight, thereby providing thermal insulation. The present layer forms the upper layer of the breathable composite film (3) formed in the final stage.

The bottom of the composite is produced with a 5-screw co-extrusion blow molding machine. The materials in different ratios are drawn to the co-extrusion heads between 205-235 °C. The values of A-B-C-D-E screws are as follows:

Screw speed for A-E is 40-60 rpm while it is 75-85 rpm for B-C-D.

Screw pressures are between 475-600 bar.

The capacities of the fans used in production are as below: o External cooling fan at 65%, o Blowing air fan at 45%, and o Suction air fan at 45%.

The bottom film is produced with a 5-screw co-extrusion blow molding machine, and the film is drawn with 500 kg/h efficiency.

Information on the formulation of 5-screw co-extrusion film:

25% A screw 50% mLLDPE + 40% calcite + 5% elastomer + 5% process auxiliary 20% B screw 50% mLLDPE + 40% calcite + 10% process auxiliary 20% C screw 50% mLLDPE + 40% calcite + 10% process auxiliary 20% D screw 50% mLLDPE + 40% calcite + 10% process auxiliary 15% E screw 35% mLLDPE + 40% calcite + 20% elastomer + 5% process auxiliary. The lower and upper layers that are obtained are combined by way of lamination. In the lamination process, the glue is fed to the breathable polyethylene+calcite (2) film. While perforated metallized polyester (1) is fed to the front of the machine, its metalized part stays inside; the breathable polyethylene film is attached to the back where the glue chamber is located, glue-coated polyethylene+calcite (2) is fed to the film surface. Values of lamination machine are set to:

Tram roller size 54 Drawing Press 5-6 bar Transfer Press 3-5 bar Winding Press 2-4 bar

With glue application (3-5 gr/m²) coils are laminated at 80-100°C oven temperature with 80m/min. For curing after lamination, it is kept in the curing rooms for 48 - 72 hours.

Thanks to the daylight reflection and thermal properties of the developed breathable composite material, with respect to products in cold transport group (2-8 °C) and cool transport group (15-25 °C), a film providing protection for minimum 6 hours for cold products and for minimum 18 hours for cool products is obtained at 60-80 °C.

Below is the comparison of test values of our invention with the most preferred equivalent product.

Below are the results of several test values of our invention.

Claims

1) The invention relates to a breathable film made of breathable composite material that will prevent the deterioration of their physical and chemical structures during the logistics activities of products that are sensitive to thermal variability, and to the method of the film formation, and its feature is that it includes the process steps listed hereinbelow:

Obtaining perforated metallized polyester (1) by making holes on the metallized polyester film, and

- Adding varied compositions of materials to A, B, C, D, E screws in 5-screw coextrusion machine, and

- Applying glue to the surface of the film in perforated structure, which contains polyethylene+calcite+additive (2), with the composition coming out of 5-screw coextrusion machine, and

- Inserting the film containing perforated metallized polyester (1) and polyethylene+calcite+additive (2) into the lamination machine together with the glue, and

- Leaving the metalized part inside while the perforated metalized polyester is given to the front of the lamination machine, and

- Attaching the film that contains polyethylene+calcite+additive (2) to the back of the machine where the glue chamber is located, and

- Applying glue to the surface of the corona-treated film containing polyethylene+calcite+additive (2), and

Laminating the coils in the laminating machine at 80-100 °C oven temperature around 80m/min, and

Keeping in curing rooms for 48 - 72 hours for curing after lamination. 2) Linked to Claim 1, it relates to a breathable film made of breathable composite material that will prevent the deterioration of their physical and chemical structures during the logistics activities of products that are sensitive to thermal variability, and to the method of the film formation, and its feature is that it includes, with the use of 5-screw co-extrusion machine,

25% A screw 50% mLLDPE + 40% calcite + 5% elastomer + 5% additive 20% B screw 50% mLLDPE + 40% calcite + 10% additive 20% C screw 50% mLLDPE + 40% calcite + 10% additive 20% D screw 50% mLLDPE + 40% calcite + 10% additive 15% E screw 35% mLLDPE + 40% calcite + 20% elastomer + 5% additive.